Time resolved photo-induced optical spectroscopy

• The perovskite layer is the photoactive material within the hybrid perovskite solar cell (HPSC) device by which the incoming photon energies are absorbed and transformed into charge carriers, and after the charge separation, the corresponding charge carriers are transported via the selective contacts for the photovoltaic operation. Optical fingerprints of these physical processes i.e. the spectral response during light absorption, charge separation, transport, recombination as well as other important phenomena such as Stark effects, electron-phonon interactions, ionic movement and Frenkel defect annihilation can be studied within the scope of time resolved photo-induced optical spectroscopy. The time scales of the main fundamental processes within perovskite solar cells directly affect the device performance, and can differ significantly from conventional solar cell technology devices. The processes varies from femtosecond to several seconds and many are strongly dependent on the chemical composition and crystal quality of the material. Full characterization of the physical properties of the device, implies a careful attention to the lifetime and amplitudes of the processes, as well as experimental design for distinguishing the processes by considering the appropriate method and/or variation in the chemical composition of the materials. Here we briefly review the relevant underlying physical processes occurring in the system, their fingerprints and how they can be detected by different spectroscopic tools, together with the methodological scopes and limitations.

Subject headings

NATURVETENSKAP  -- Fysik -- Atom- och molekylfysik och optik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Atom and Molecular Physics and Optics (hsv//eng)

Keyword

Stark effect

Photo induced absorption

Charge carrier dynamics

Ionic movement

Defect annihilation

Electron-phonon interaction

Publication and Content Type

ref (subject category)

kap (subject category)